Spring suspension for motor vehicles



Sept: 18, 1928. 1,684,692

J. F. ADYE 4 SPRING SUSPENSION FOR NOTOR VEHICLES Filed 001:. 21, 1925Patented Sept. 18, 1928 messeorrres,

Jofii r Em ts of smelt: memes? spams SUSPENSION sombre-e v einctes.

Aijplication-filedfletoter 21; 1925, Serialiio. 63,9'i4; a1id ifi eeeatBritain OttbH'r 27,1924;

This'inventioh is for improvements in or relating to spring-suspensionsfor motor andlike vehicles, and has for its object to provide animprovedcon'itruction ofthe sa'me whereby the vertical movement ofi'anyone' wheel is controlled by the joint action of the springs'formore thanone WheeLo'r-m other words-the combinediflexibilities of more thanone-spring are utilized jointly; this enables the displacement of thevehicle-bodyfor any given irregularity of the surface o'n'which itisrunningv-"to' be less than that'obtai'ned with other known-fonns ofsprings', or al ternativelyto bc'so modified that the discomfort-.oft'hepassengers inthe vehiele is reduced. A further object is to provide ,a'

construction in which the weight vof the springs thems'elv'esand theirassbciated'parts whereby the vehiclerframe is'supportdon the'aXles,isless than is required with or dinary-forms of springingr A-furtherobjectis'to provide a combina"-' tion'of springsllavingdifierentnatural period's of oscillation controlling'ea'ch axlein order to tend'to'prevent' and damp out vibration antl'the naturaltendency to swing F urther,-

ingor bouncing;- of the vehicle. provision-towards this-endmay' be madeby thearrangement ofa tO'g-glede'verage to portions of'thesprin'gsyso asto give a varying resistance to the springs concerned which varies in agr'eater'proportion than the'normalkresistanc'e of the spring alone.

According td-this'invent-ion there is pro-' vided in'ua vehicle,the-combination with a' spring for one wheel (such as acantileverspringtfdr front wheel) and a springfor another wheel (such asa rear wheel-on-the same-{side of the vehicle). of means interconneetinnthe saidsprings whereby; a springgnided and controlled verticaldisplacement of one wheel tends to produce a displacement ofthe otherWheel in the opposite direetion,-w'hereby-the springs of both Wheels areoperative to control the movement of either wheel; that is to say, ifthe'one wheel is forcedupwards from its-normal position by encounteringan obstacle, the other wheel is pressed downwards;with the resultthatthe rear'endof the vehicle is slightly raised; W here frontand rearwheels are'thus interconnected,- the effect of the upward movementimparted tothe front wheel is distributedtoboth'springs so that only apart of that movement is transmitted to the front of the vehicle frame,-the" other partbeing operative tolift therear end of the'vehicleframe,so that the tot'ah movement; being 'dis tributed o'ver'the whole frame,can be reduced in extent, or alternatively more flexible springs canb'eE usedr 1 Additional leaf-springs may be provided to serve asguidesfor theaxles; and' the'interconnection aforesaid may be such as totransmit to the other springs? a moveme'nt which isproportionatelysmaller, as" the do flection of one=spring isdncreased.

, The invention' furthereoitiprises the combination in ;a"vehicle,-withtvvoisets of parts asset forthabove, one setbeing'sit'uated on each-sideof the vehicle,- of means interconnecting-the Said-sets of partswherebya' displacement of onewheel, say=for example,

afrontvvheel,- tends to produce adisplacement in the same direction ofthe corresponding wheel; t thafi'is? to isayythe, other front Wheel,'on'the other; side of the vehicle; the two wheelsat theother endof'the'vehicl'e receive a'tend'ency tomove together-in the oppositedirection.

,-VVhen the invention is' applied-to a vehicle havingsemr-elliptmsprings, one end: of the forward spring and one end of the rear springare each connected respectively" to arms of bell-crank levers vhereof'theother arms are connected together by a tie-rod;

cable or resilient tension device such as' a spring; The bell-cranklevers may be con structed each with an obtuse angle in order to givestability to the whole arrangement and the tie member between thebell-crank levers may be connected to a rocking-lever or equivalentdevice extending across the frame to the corresponding parts on theother'side of the vehicle;

This invention also-covers a specific construction in which forward andrear cantilever springs are rigidly fixed to the vehicle frame and theinterconnecting means aforesaid'between the springs is constituted' by atie-member which issecured at its ends to the springs at or near thefree ends'thereof and is guided intermediately ofits ends to cause it tobe inclined to the springs themselves at its connection With them. Thetiemember connecting the springs may'beitself resilient; andit's'guiding means may be constituted by radius-rods pivoted on thevehicle-frame, or by flexible SPtiIigsWhiCH'WilI give an equii'alenteffect.

According to another feature of this invention, the tie-member aforesaidis operatively engagedwith a rocking-shaft or ether device which-extendsacross the vehicle and constitutes the interconnecting means-between thespring mechanism on the two sides 7 of the vehicle.

In the case of a vehicle m which the front and rear cantilever-springsare each pivoted or. thesvehicle-framev intermediate of its ends,

the wheels being engaged by the forward end of the front spring and therearend of the rear spring, the otheraends of the cantilever springs,which are mutually adjacent one another, are .connected respectively inaccordance .with this. invention .to the opposite ends of arocking-lever which is pivoted in;

l'ermediate of its ends.

-Therocking-lever may beiarranged with its arms-inclined to one anotherso that each of them slopes from the pivot-point towards the=spring towhich it isconnected, thereby providingfimore stability :to the systemiAlso, the leven itself may be:so constructed as'to be .resilientfitThe'stability may be still further-enhanced.by 'the provision of a leaf-. orother spring-connected to the lever in such manner as to =yieldinglyhold it in:

itsmeanposition; aisi milar eifecttmay be obtained by leaforothersp'rings operatively connected to the axles or the main cantileversprings in a similar manner.

With this arrangement the interconnec tion between the spring mechanismof the two sides of the vehicle :may be effected according to anotherfeature of'this invention, by fixing the-respective rocking-leversaforesaid one. single'sha ft' extending across'the vehicle-body. Y

The accompanying drawings, Figures 1 to 8, illustrate diagrammaticallyvarious arrangements of springs in accordance with this invention, butthe invention is not limited to these particular arrangements. Thus, forexample, a part of the construction shown in one figure may be combinedwith a part of a construction shown in another figure.

In said drawings:

Figure 1 shows one construction according to the invcntion comprisingcantilever shown in Figure. 1 but reinforced by similar springs andinterconnected by means comprising a bell-crank lever;

F i re 4 shows-"another construction applied -to the two front wheels ofa vehicle and comprising an inverted semi-elliptic spring whereof theends are interconnected by means comprising bell-crank levers and atension member;

Figure 5shows another construction comprising two cantilever springs ofdifferent construction pivoted to the frame and connected together byaninextensible tension rod 1 Figure 6 shows another c on.structioncom-.

prising light springs of different construe tion connected-together byinter-connecting means and an extensible'tension rod; Figure 7ilustrates another construction similarto i that shown in Figure 5,-bi1t :having interconnecting means -zcomprising a hell-crank levels-andl4 n Figure 8 shows a further construction sim ilar to that showninFigure7-but =comprising semi-elliptic springs'teonnected'ftogetherbyxmeans of -a-rocking :lever' arm mounted on the frame. l

Like reference numerals designate similar parts throughout the several-'viewsi -Referring first "to 'Figure 1, the vehicleframe is indicatedbythe reference 10 and the front and rear axles by the references 11, 12respectively. The axles are each mounted upon a cantilever-spring 13which-may be only a single leaf or plate and is rigidly fixed at one end14 tothe vehicle-frame-and at the other end-lfi'to the axle.- Thesprings are each preferably sloped downwardly from the frame to-the axlewith a: reverse curvature, and it will be appreciated that with such ana.ri'angement*the spring-controlled movement of the axle is not a plaincircular movement about the point 14 or such as is obtained when theaxle is controlled by a rigid pivoted radius-rod. A tie-memher 16 whichmay take the form of a coil- 1-:prlflg as shown in Figure 1, so as toboresilient, or may be inextcnsible, in which case it may takethe formof a thin leaf of spring steel, or rod, is secured to the front axle 11with the main spring 13, and this tie-member extends from the front axlerearwardly sloping downwards to a point determined by a strut-member 17.This may take the form of a spring on rigid radius-rod pivoted on theframe 10, or it may be constituted by a spring, whereof the flexibilityallows the .riangular structure 13, 16, 17 to yield and iet the frontaxle 11 move relatively to the rame. From this strut-member 17 thetiemember 16 is continued rearwardly by a part 18 which may beresilient, as shown, or may be inextensible, and is connected at itsrear end to a similar set of parts'for the rear axle. Similar referencesare attached to the similarpartscoupled to the rear axle,

but. in" the case otthe strutl'? a possible modification of the shapehas been illustrated. Where the two members 18' are connected togetherat 19 they may engage an arm 20 '(for example, by a l'iook sh aped endon each engaging; a bush on'the arm) which is mounted on a shaft whichcxtonds'across' the vehicle-frame and carries a similar'arm similarlyconnected to a spring suspensionon the 'otlier'side ot the vehicle,this'latter being similar to that already described; These arms 2O maybe of less length than the struts 17, to'give stability to the system,and 'they need not be rigidly connected to the cross-shaft.

The member 17 whichac'ts asa strutmay be-so' disposedthat it-liesat anobtuse angle witli the cantilever-spring 13; for the purpose" of' givingincreased stability to the whole arrangement.

If thecantil'ever springs 'Lrarc' only single" leaves; it maybe-considered desiiable-to provide' a safety-'--clevice, in case-ofbreakage? Thismay take-the form ofasecond"leaf-' s rin secured to theaxle and extcn'din under the main-spring13towards and close up o the'-frame inorder to take'thecom p'ressivel'oad in the member; the'free'end of this -spring is; shackled to theendof another spring abovethe main springand tiked' to-the frame, sothat ifthe main spring breaks, the shacltl'e Will swing into" a stable position incontact with thebroken main spring andtake the load;

Again'g-at the=portion of the guide spring,-

adjaoent 'to the abutment, which, in a parallel-seotitm spring is-themost highly stressed portion, a safety device may -be provided by fixingga covering-sheath over this 7 portion so that in the eventofa'breakage the springbeingsubjeot ma compression force-cannot moveout-of position, and thereforeby the abutment: of thebroken 'ends'willstill transmit the compressive load.

It will be seen that with the arrangementillustrated in Figure 1, if oneof the front wheelsof the vehicle meets an obstacle which oausesit torise, the triangular frame 13, 16, 17 is distorted as theaxleri'ses andtension is put'upon the member 18 and trans- Inittedthrough itto thespring-mountingfor" the: rear axle oathe same side ofitQthe effectbeingatendency to depress the rear wheel or, what is equivalent, raisethe rear portion of movement tothetns'ion member' l9 and therefore anincreasing resistance to the movement of theaxl'e 11.v

The interconnection'of the springsystems on the two sides of the vehicleby the armsj f-(l'and the'cross shaft whereto they are'fiiied ensuresthat'the movement aforesaidof one front wheel is'transm' ttcd' to theother'side of the vehicle, tendingto raisethe' other front Wheel anddepress the other rearwheel. I

If it is desired, the at'ritn'gei'n'ent" illustrated in Figure 1may'hzive pivoted' radius rods associated with the axlesto gnidtitheirmovement, although this isn'ot essential, as the'rigid fastening ofthe-cantilever-sprin s" 13 to' the vehicle-frame andi"the"axledrootively reshains" the axle against" any movement laterallyofthevehicle.'

Figure 2 shows a modified arran e'mcnt in l which the front andrearaxle'S' 12 are supported on semi=elliptiosprings which'arcinterconnected by means of bell 'crailkievers' 21, 22, and" a tensionmembefifl E This tensionmember may talietlie forniof 'an in} 9extensible rod,'gor it may be resili'eht-.Y* The bell crank levers mayeach have'tliei'r arms inclined to one anotherafian,obtuse"an rle," soas toincrease the stability" of--the-Wlible system. A transverse'shaftfl' i 'ifiafybeused' to interconnect thespring systetii'son the twosides of the vehicle, and tl1e arm"25?connected to thetension-memberfl?) may be made somewhat shorter than the' 'arnis at thebell-crank-levers 21,92, alswfor' tliepui'pos'e mo of giving'increasedstabilityz' Pivot'edarx'ns' such as25 maybe 'used fbr'th'e samep'urp'o's'e' independently of the interconneccion be tween the twosides-of thevehiclet" The" action of this system'of springingisexa'ctlyfthe same as that described above' 'w'itliaf erence-to Figure-l, andneednot be repeated.

Figure -3shows another arran ement some-'- what similar to thatillustrated inFignre 'l, but each of the cantilever-sprin s-lfi which isattached to the-uppersideoFan-axle, is re nforced by a similarSpring'QGattItChed to the-lower side of the axleorin'anyothc rconvenient manner and so mo'unted'orr the" vehicle fram'e 10 as to besubstantially par allel with the spring 13. This arrangement ensuresthat the vertical axis of the axle receives asubstantially parallelmovement.

Another modification is alsoillnstratedfinthis figure, in'that the twotension members 18, instead=of being connected together and to aradius-arm 20, areconnected 'to'two arms of a bell-crank lever 27, 28,which may" be mounted on a shaft 29exten'ding'across the vehicle-frame.With-thisarrangementincreased stability of the system is obtained sincethe turningefiort exerted bytension' of the member 18 on tlie-arm 27 hasa gradually decreasing moment, whereas the" moment of the force actingon th'e'a-r'mQS elliptic spring 30 rigidly secured to the vehicle-framehas its ends coupled to bellcrank levers 31, 32 respectively, pivoted onbrackets on opposite ends of the axle 33.

.The other arms of these bell-crank levers 34,

respectively are coupled to one another by a tension-member which may beinextcnsible or, asillust-rated, may take the form of a tension-spring36. If one wheel is displaced, say, upwards, by encountering anobstacle, say, the right-hand wheel, the corresponding half of thespring is deflected as a cantilever-spring but the bell-crank lever 31,34 is rocked on its pivot and transmits a pull through the member 36 tothe other bellcranlilever 35, 32, which thereupon brings about arelative displacement of the lefthand wheland: its end of. the spring31), in the oppositedirectionf So far as these .two wheels areconcerned, ,the effect of the arrangement is the same 'asthatillustrated in Figure l. .A- radius-rod 37 .may be pivoted onthetframel0 and connected to the mid-point .ofthe tension-member. 36,and this rodima be interconnected by means of a longitu inal shaftwhereon it is fixed with a similar springing arrangement for the wheelsat theother end of the vehicle.

It also lies within the scope of this invention to combine aspring-suspension such as illustrated inFigure 4, but without theinterconnection between .the front and rear wheels aforesaid, with aspring-suspension such as illustrated in Figure 1, but without v theinterconnection between the two sides of the vehicle. v D

Figure 5 illustrates yet another modifi cation. The front and rear axles11, 12 are each mounted upon cantilever-springs 38, 39 Whicharepivotally-connected to the vehicle-frame and have short arms 40, 41coupled together by a tension-member 42. This tension-member may beinextensible like a rod, or may be resilient, as in thepreviously-described constructions. Also, it may be interconnected withthe suspensions for the wheels on the other side of the vehicle.Alternatively, the interconnection between the two sides of the vehiclemay be effected by making the cantilever-springs 38, 39 fast 011 theirrespective pivotal rods and extending these rods across the vehicle tocarry the corresponding springs at the other side. In such anarrangement a single interconnecting member 42 may be used, this beingoperative in any convenient manner on the two cross-shafts, say onlevers at the middle of the length of each shaft, or one on either sideof the vehicle; similarly, the two springs 39 may be made fast on theirpivotal rod which extends across the chassis and the remaining springsfor the other axle connected to levers on this pivotal rod. Twodifferent forms of cantilever-spring are illustrated; the spring 38 hasits leaves extended and bent over to form the short arm of the lever,whereas the spring 39 is mounted in a bracket having a rigid arm 41 tocon-' stitute the short arm of the lever. The guiding of the axle in avertical plane may be further effected either by means of a singleleaf-spring 43, as shown in the lefthand ofFigure 5, this leaf-springbeing rigidly secured at its ends to a bracket on the frame 10 and tothe axle 11, or, as shown at the right-hand end of Figure 5, byextending one of the leaves of the spring 39 backwards, as shown at 44,and coupling it by a suitable shackle to the vehicle-frame. Theguide-spring need not be only a-' single leaf for an increased number ofleavesmay be used with the object of increasing the stability of thesystem and providing that a reduced portion of the loading of one axleor wheel is transmitted to another axle or wheel. 7

This invention also covers constructions whereof one is illustrated inFigure .6 in which the springs are similarto those used in ordinarysystems of springing and are constructed so lightly as to be incapableof themselves of withstanding the stresses to which they are subjected,but they are interconnected, in the manner hereinbefore described, bypreferably resilient means which provides the additional strength thatis required. In the arrangement illustrated the frame 10 is provided atthe front with semielliptic springs 45 and at the rear withcantilever-springs 46, these being similar in arrangement to the kindsordinarily used, but more lightly constructed. The axles areinter-connected by means of bell-crank levers 48, 49, and 50, 51, thearms 49, 51 being connected by a tension-spring 52. With thisarrangement any displacement of, say the front axle 11 is resistedpartly by the spring 45, partly by the tension-member 52, and partly bythe spring 46, and at the same time the movement of the vehicle-frame isdistributed instead of being concentrated at the front end. IVhilst suchan arrangement would operate even if the -ten-' springing isexaetlyrthesame asthatde'scrib- .in detailed arrangement. sothatdifferent .types of springs may. be employed. For ex- .amplein theconstructiongiven in .Figure 15, the-spring levers 38,:4'O or'39,-41 maybe reversed-so that the shorter arms extend in an upward vdirection andengage comq wrcssion 'spnings. suit-ably ,arranged. 1 Again,gawpplementary-spiral springsfianay -be .xar-

edwvii-hae'ferenee tdiF- igurehl and titaneed not he repea,-t;ed;m;,detail. -;If-desired. .a flat leafi$pr1r1g=60 provided asin ,the' manner ihereinbefore describedgto act asa :guide vto the axlein its vertical movementrandetihe .belhcrank-leveri57;, 58 niay-hecontrolled by a flat spring 61 secured on it and anchoredatitheotherniend lto theivehicle frame 10. This spring tends to maintainthe whole system in its mean position. Inter-connection between thesprings on the two sides of the vehicle may be provided by means of across-shaft 59 to which the bell-crank levers 57, 58 on each side of thevehicle are connected.

Figure 8 shows an arrangement which is similar to Figure 7, except thatsemi-elliptic springs are used instead of cantileversprings. Thesemi-elliptic springs 62, 63 are connected at their forward and rearends respectively to the vehicle-frame in the usual manner, but theirrear and forward ends respectively are shackled to a rocking-le er 64which may have its arms inclined to one another to provide stability forthe system. This lever may be interconnected by means of a cross-shaft65 with a similar lever on the other side of the vehicle, and the actionof this arrangement of springs is again similar to that of thearrangement previouslydescribed.

In any of the foregoing constructions, wherever a limited pivotalmovement is required this may be provided by a suitable arrangement ofspring members in order to avoid the use of joints which requirelubrication. such for example as a flat spring secured at one end to thevehicle-frame and at its other end to the main spring, the abuttingsurfaces of the two springs being formed "with a slightly convexcurvature.

In some constructions of motor vehicle, the frame-members are notparallel with one another but diverge towards the rear, and whilst thesprings for the front wheels are parallel with one another, those forthe rear wheels diverge towards the rear. The present invention may beapplied to such constructions, since the tension-members, such as 18. onone side of the vehicle, need not necessarily be in line with oneanother, provided they are connected to a radius-member, such as 20 inFigure 1, or by other suitable means. Also, of course. the system can beapplied to a two-wheeled vehicle. or to vehi cles in which driving andbraking are applied to more than two wheels. for the pur pose ofequalizing the loading on the wheels.

Additional leaf-springs substantially parallel to the main leaf-springsmay be provided to an axle (or suitable radius-rods) with the object ofproviding a means of resistingl-the torque set up by either driving ofbraking loads.

Any of the constructions-may be modified ranged as an anchorage to theframe from any suitable portion of the moving mechanism in any of theconstructions.

An important advantage pertaining to this invention is that whilst theflexibility Of the spring suspension can be increased, as regards thedisplacement of a single wheel, the resistance to rolling of the frame,when both ends of one side of the vehicle are similarly andsimultaneously affected need not be diminished. and the same applies tobouncing, when both axles move similarly and simultaneously.

It will be seen that the present invention provides a system ofspringing whereby the spring-controlled displacements of a wheel aretransmitted to the vehicle-frame in such a manner that the frame remainsapproximately level even if only one wheel be displaced; as a result ofthis, the vertical movement of the frame is considerably reduced, andless power is required to propel the car, since the mass moves morenearly in a straight line than with known springing systems. In all thecases where single leafsprings are used, the springs are frictionless inoperation and are very sensitive to irregularities in the road-surface.There is no necessity for lubricating the springs, and they can hepainted with the frames and are easily washed and kept clean. Also, thesprings can he designed to have an increased period. of vibrationwithout making them unduly long. Finally, owing to the displacement ofany one wheel being distributed over the whole frame, the frame itselfis not racked or twisted to the extent that is ordinarily obtained.

\Vhat I claim as my invention and desire to secure by Letters Patentis 1. In a vehicle, the combination with a main frame, of awheel-carrying axle, a spring operatively interposed between said axleand said frame, a second wheel-carrying axle, a second springoperatively interposed between said second axle and said frame. andmeans comprising two lever arms pivot ed on said frame and operativelyconnected together at one end, each lever arm being associated with oneof said springs. said lever arms being so inclined with respect to eachother, and being so disposed with respect to the frame and the springsthat displacen'ient of one axle tends to produce a i progressivelyvarying and opposite displacement of the other axle.

:-= '2.-In a vehicle; thecombination with a fmain frame, of awheel-carrying axle, a-

spring operatively interposed between said -=axle and said frame,fa'seeond wheehcarryin :vaxle; a second spring'operatlvely mterposecibetween-wsaid second axle and saidframe, meanseomprising abell cranklever pivoted Ben said irame each arm of 'saidlever being connected withone of .said spr1ngs,- sald arms being so inclined with respect toeachother, andbeing so disposed with'respect t0 the frame and the springsthat displacement :of one axle tends to produce a progressivelyposition.

Intestimony whereof I aflix' my signature.

JOHN FIFI'ELD'ADYE.

